Process of fabricating beryllium plate member with large mechanical strength

Abstract

A method for fabricating a beryllium or a beryllium alloy thin plate member for uses requiring great mechanical strength, such as X-ray aligners. A beryllium or a beryllium alloy is deposited on a base structure, and the base structure is then etched away to leave the thin film. However, bubbles or hollow spaces form in the thin film during the deposition stage. The thin film is shaped by using hot rolling, thereby improving the density and accordingly the mechanical strength.

What is claimed is: 
     
       1. A process of fabricating a high-density metal plate member, comprising the steps of: preparing a base structure by covering a substrate with a protection film;   depositing a metal film of a substance selected from the group consisting of beryllium and beryllium alloys;   removing the base structure; and   rolling said metal film so as to increase its density.   
     
     
       2. A process of fabricating a high-density metal plate member as set forth in claim 1, in which said substrate is formed of a metal selected from the group consisting of copper and nickel. 
     
     
       3. A process of fabricating a high-density metal plate member as set forth in claim 2, in which said protection film is formed of silicon. 
     
     
       4. A process of fabricating a high-density metal plate member as set forth in claim 2, in which said protection film is deposited on said substrate by using a vacuum evaporation technique. 
     
     
       5. A process of fabricating a high-density metal plate member as set forth in claim 4, in which said metal film is deposited on said protection film by using a vacuum evaporating technique. 
     
     
       6. A process of fabricating a high-density metal plate member as set forth in claim 5, in which said substrate is etched away by using a nitric acid and in which said protection film is removed by an ion milling technique. 
     
     
       7. A process of fabricating a high-density metal plate member as set forth in claim 6, in which the step of rolling said metal film comprises a plurality of hot rolling stages and a plurality of annealing stages each carried out after each of said hot rolling stages. 
     
     
       8. A process of fabricating a high-density metal plate member as set forth in claim 7, in which said hot rolling stages are repeated until said metal film is laminated to a thickness ranging between about 0.005 millimeter and about 0.05 millimeter. 
     
     
       9. A process of fabricating a high-density metal plate member as set forth in claim 7, in which said process further comprises the step of shaping said metal film with static hot water having a temperature of about 1050 degrees in centigrade and at about 180 MPa carried out before the step of rolling metal film. 
     
     
       10. A process of fabricating a high-density metal plate member as set forth in claim 7, in which said process further comprises the step of finishing said metal film by using a cold rolling technique. 
     
     
       11. A process of fabricating a high-density metal plate member as set forth in claim 7, in which said process further comprises the step of finishing said metal film by using a hot rolling technique. 
     
     
       12. A process of fabricating a high-density metal plate member as set forth in claim 11, in which said metal film is finished to a thickness between about 0.002 millimeter and about 0.05 millimeter. 
     
     
       13. A process of fabricating a high-density metal plate member as set forth in claim 7, in which each of said hot rolling stages is carried out between about 100 degrees and about 600 degrees in centigrade. 
     
     
       14. A process of fabricating a high-density metal plate member as set forth in claim 13, in which the reduction of the material thickness in each rolling stage ranges between 20% and 50%. 
     
     
       15. A process of fabricating a high-density metal plate member as set forth in claim 14, in which the annealing stage after the first hot rolling stage is carried out between about 600 degrees and about 850 degrees in centigrade. 
     
     
       16. A process of fabricating a high-density metal plate member as set forth in claim 14, in which the hot rolling stages except for said first hot rolling stage are respectively followed by the annealing stages carried out in an argon ambient between about 600 degrees and about 900 degrees in centigrade. 
     
     
       17. A process of fabricating a high-density metal plate member, comprising the steps of: (a) preparing a base structure;   (b) depositing a metal film of a substance selected from the group consisting of beryllium and beryllium alloys on the base structure;   (c) removing the base structure;   (d) rolling said metal film so as to increase its density;   (e) shaping said metal film into a disk which forms a window of an x-ray aligner.